Terms of Service

Last updated: September 5, 2026

These Terms of Service (“Terms”) are an agreement between you and Trisdia, LLC (“Trisdia,” “we,” “us”), the company that makes and publishes Lexxio. They cover the Lexxio app on desktop and mobile, Lexxio Verbs, the Lexxio Lens browser extension when it is available, the Lexxio Originals, and this website at lexxio.ai (together, the “Service”). By creating an account, joining the waitlist, buying a plan, or using any part of the Service, you agree to these Terms and to our Privacy Policy. If you do not agree, do not use the Service.

1. Who can use Lexxio

You must be at least 13 years old to create an account. If you are between 13 and the age of majority where you live, you may use the Service only with a parent or guardian who agrees to these Terms on your behalf. Children under 13 may use Lexxio only through a parent or guardian’s account, with that adult present as the account holder; Lexxio’s supervised mode exists for exactly this. The adult is responsible for the account and for everything done under it. We do not knowingly let anyone under 13 hold their own account.

2. Your account

  • Much of Lexxio works without an account. An account is needed for paid plans, cross-device sync, and certain Originals whose text is delivered encrypted.
  • Give us accurate information, keep your login secure, and tell us promptly if you think it has been compromised. You are responsible for activity under your account. One person per account: do not share it or sell access to it.
  • You can delete your account from inside the app at any time. Section 10 explains what deletion does and does not remove.

3. Plans, allowances and billing

Plans

Lexxio has a free tier and paid plans (currently Reader and Pro). What each plan includes is described on our plans page at the time you buy and may change for future billing periods as the product evolves. Reading, flashcards, the Basics course and the verb curriculum do not draw on any allowance. AI work (translating, explaining, looking up, reviewing, conversation, and similar) draws on a monthly allowance that is expressed in approximate pages. It is an estimate: dense text, structured output and languages further from English use more of it than plain prose does. The allowance resets each billing cycle, does not roll over, and has no cash value. When it runs out, the AI features pause until the next cycle and everything already generated stays available.

Subscriptions

  • Subscriptions to Lexxio are billed on the web through Stripe. They renew automatically at the then-current price for your plan until you cancel. You can cancel at any time from the billing portal linked in the app or on this site; you keep access through the end of the period you have paid for, and no partial refund is owed for the remainder.
  • Introductory or early-access pricing applies for the period we state when you sign up (for example, the first twelve months) and then converts to the regular price for your plan. We will tell you before a price you are paying changes, and you can cancel before it takes effect.
  • Prices are shown before any tax we are required to collect. If a payment fails, we may retry it and may suspend paid features until it succeeds.
  • Refunds are not automatic, but if something went wrong, or the product did not do what we said it would, write to us and we will sort it out. Where the law where you live gives you a right to withdraw, nothing here limits it.

Lexxio Verbs and other app-store purchases

Lexxio Verbs is sold as a one-time purchase through the Apple App Store and Google Play. Those purchases are made with Apple or Google under their terms, and refunds for them are handled by Apple or Google under their policies. Where a Lexxio subscription is ever offered through an app store, the same applies to that subscription.

Codes, trials and complimentary access

A code printed in one of our books, or given to you by us, unlocks what the code says it unlocks, once, on one account. Codes may not be resold. Trials, promotions and complimentary access are at our discretion, may carry their own conditions, and may end when we say they end. We may cancel any code or access that was obtained fraudulently or shared beyond what it was meant for.

4. Fair use of the AI features

The AI features run on metered infrastructure that we pay for per request. In addition to your plan’s allowance, there are per-user rate limits and daily caps on individual features, and service-wide ceilings that protect the whole user base from a runaway. We may throttle, queue or temporarily refuse requests to keep the Service healthy, and we may change models, providers and limits without notice. Do not use scripts, bots or other automated means to access the AI features, do not attempt to reverse-engineer or bypass the limits, and do not resell or redistribute the output as a service.

5. Books you bring in

  • You can import your own EPUBs and text. You are responsible for having the right to read, translate, store and listen to anything you import. Do not import content you are not entitled to use.
  • Imported books, their translations and their audio live on your device. We do not upload or host your books. Moving a book to another of your devices happens directly between them on your own network; the bytes never pass through us.
  • The public-domain library is fetched by the app directly from Project Gutenberg. Those works belong to the public domain; we do not own them, claim them or control their availability, and Project Gutenberg’s own terms apply to the download.

6. Lexxio Originals

The Lexxio Originals are fiction published by Trisdia, LLC. Each title, in every language and at every reading level, together with its artwork, recorded narration and quizzes, is protected by copyright and belongs to Trisdia. Your plan or borrow gives you a personal, non-transferable licence to read and listen to an Original inside Lexxio for as long as you have access to it. You may not copy, extract, redistribute, publicly perform or use an Original to train a model. Some Originals are delivered encrypted and require an account; do not attempt to defeat that. Borrowing limits and which titles are free may change. Printed editions of the Originals are sold separately and carry their own copyright notice.

7. AI-generated content

Translations, reading-level adaptations, explanations, definitions, quizzes, Coach’s plans and messages, the characters you speak with in Talk, and pronunciation scores are produced by machine learning models. They are learning aids. They can be wrong, incomplete, biased or oddly phrased, and they are not a substitute for a qualified translator, teacher, or any professional advice. Check anything that matters. As between you and us, you own the output produced for you, subject to the rights of the underlying model providers and to Section 6 for the Originals. You may not use audio generated by the Service to train or improve a speech or language model.

8. Acceptable use

Do not use the Service to:

  • break any law or infringe anyone’s rights;
  • upload or generate content that is unlawful, hateful, sexually explicit involving minors, or that harasses a real person;
  • probe, overload, scrape or interfere with our infrastructure, or access it other than through the app and site we provide;
  • bypass a PIN, an encryption scheme, a borrow limit, an entitlement check or any other technical measure;
  • reverse-engineer, decompile or extract the app, its models, its voices, its dictionaries or its content, beyond what law expressly allows;
  • share an account, or resell access to the Service.

9. Intellectual property

The Lexxio app, Lexxio Verbs, Lexxio Lens, this website, the Lexxio name, wordmark and artwork, the Basics course, the verb curriculum and the Originals are owned by Trisdia, LLC or its licensors and protected by copyright, trademark and other laws. We grant you a limited, revocable, non-exclusive, non-transferable licence to install and use the app for your own personal, non-commercial language learning. Your notes, vocabulary, progress and the books you imported are yours. If you send us feedback or suggestions, you let us use them without obligation to you.

10. Ending things

  • By you. Stop using the Service whenever you like. Delete your account from Settings in the app. Deletion removes your login, profile, device list and synced progress from our servers. Billing and usage records (subscriptions, purchases, credit grants and charges, and the metadata of AI requests such as model, token counts and cost) are kept for accounting, tax and dispute purposes but are severed from your identity, so they no longer point at you. Books and data on your own devices are yours to keep or wipe.
  • By us. We may suspend or end your access if you breach these Terms, if we are required to by law, or if we reasonably believe your use puts the Service or other users at risk. Where practical we will tell you why. If we end a paid plan for a reason that is not your breach, we will refund the unused part of the current period.
  • Shutting down a feature. Lexxio is a small company’s product and it changes. We may add, alter or retire features, models, voices, languages and titles. If we retire the Service entirely, we will give reasonable notice and a way to export your data.

11. Early access and beta software

Parts of the Service may be labelled early access, beta, preview or TestFlight. They are unfinished by definition. They may be unstable, change without notice, lose data, or be withdrawn. Keep backups. Apple’s TestFlight terms apply to TestFlight builds.

12. Updates and third-party services

The desktop app checks for updates and may download and install them. The Service relies on third parties we do not control, including Stripe, Apple, Google, Supabase, Cloudflare, OpenRouter and the model providers behind it, Microsoft Azure, Sentry, Vercel, Project Gutenberg, Wiktionary, GitHub and Hugging Face. Their availability and terms affect the Service, and an outage or change on their side is not a breach on ours. Our Privacy Policy lists what each one is used for.

13. Disclaimers

THE SERVICE IS PROVIDED “AS IS” AND “AS AVAILABLE.” TO THE FULLEST EXTENT PERMITTED BY LAW, TRISDIA DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, TITLE, NON-INFRINGEMENT, AND ANY WARRANTY ARISING FROM COURSE OF DEALING OR USAGE. We do not promise that the Service will be uninterrupted, error-free or secure, that AI output will be accurate, or that you will reach any particular level in a language. Some jurisdictions do not allow certain disclaimers, so some of this may not apply to you.

14. Limitation of liability

TO THE FULLEST EXTENT PERMITTED BY LAW, TRISDIA AND ITS MEMBERS, EMPLOYEES, CONTRACTORS AND SUPPLIERS WILL NOT BE LIABLE FOR ANY INDIRECT, INCIDENTAL, SPECIAL, CONSEQUENTIAL, EXEMPLARY OR PUNITIVE DAMAGES, OR FOR ANY LOSS OF DATA, PROFITS, GOODWILL OR USE, ARISING OUT OF OR RELATING TO THE SERVICE, HOWEVER CAUSED AND UNDER ANY THEORY OF LIABILITY, EVEN IF ADVISED OF THE POSSIBILITY. OUR TOTAL LIABILITY FOR ALL CLAIMS RELATING TO THE SERVICE IS LIMITED TO THE GREATER OF THE AMOUNT YOU PAID US IN THE TWELVE MONTHS BEFORE THE CLAIM AROSE OR FIFTY US DOLLARS (US$50). These limits do not apply to liability that cannot be limited by law.

15. Your responsibility to us

You will defend and indemnify Trisdia against claims, losses and reasonable costs (including legal fees) arising from content you import into the Service, your breach of these Terms, or your violation of law or of someone else’s rights.

16. Disputes and governing law

These Terms are governed by the laws of the State of Washington, USA, without regard to its conflict-of-law rules, and by applicable US federal law. Before filing a claim, contact us and give us thirty days to try to resolve it informally; most problems are a conversation, not a case. If we cannot resolve it, claims will be brought in the state or federal courts located in King County, Washington, and you consent to their jurisdiction, except that either of us may bring an eligible claim in small-claims court, and nothing here stops you from relying on mandatory consumer-protection law where you live. To the extent permitted by law, you and Trisdia each waive the right to bring or take part in a class or representative action against the other.

17. Apple and Google terms

If you obtained an app through the Apple App Store: these Terms are between you and Trisdia, not Apple; Apple has no obligation to provide maintenance or support; Apple is not responsible for any claim relating to the app, including product liability, regulatory non-compliance or intellectual-property claims; and Apple and its subsidiaries are third-party beneficiaries of these Terms and may enforce them against you. You represent that you are not in a country subject to a US government embargo and are not on any US government list of prohibited parties. If you obtained an app through Google Play, Google’s terms also apply to that purchase.

18. General

  • These Terms and the Privacy Policy are the whole agreement between you and Trisdia about the Service and replace any earlier terms.
  • If a part of these Terms is unenforceable, the rest still applies. Our not enforcing something once is not a waiver.
  • You may not assign these Terms. We may assign them to a successor of the business.
  • We may change these Terms as the product evolves. We will update the date at the top, and for material changes we will give notice in the app, on this site or by email to account holders before they take effect. Continuing to use the Service after that is acceptance.

19. Contact

Trisdia, LLC
hello@trisdia.com
or the contact form on this site.